Method for preparing black fibers

Abstract

A method for preparing black cotton-like fibers is provided, using a DTY texturing process, wherein POY and FDY fibers containing carbon black are sequentially passed through a first yarn guide, a yarn guide roller, a tensioner, a first yarn feeding roller, pre-entangling, a second yarn feeding roller, a first deformation hot box, a cooling plate, a false twister, a third yarn feeding roller, a middle entangling device, a setting hot box, a setting yarn feeding roller, oiling, and winding to obtain a black cotton-like fiber; the first yarn guide is a yarn guide wheel; a tow contacts a groove bottom of the first yarn guide in the process of movement, driving the first yarn guide to rotate; and the tensioner is a magnetic tensioner.

What is claimed is: 
     
       1. A method for preparing black fiber, using a drawn textured yarn (DTY) texturing process, wherein a polyester pre-oriented yarn (POY) fiber and a polyester fully drawn yarn (FDY) fiber are sequentially passed through a first yarn guide, a yarn guide roller, a tensioner, a first yarn feeding roller, pre-entangling, a second yarn feeding roller, a first deformation hot box, a cooling plate, a false twister, a third yarn feeding roller, a middle entangling device, a setting hot box, a setting yarn feeding roller, oiling, and winding to obtain the black fiber;
 wherein the polyester POY fiber and the polyester FDY fiber both contain carbon black; 
 wherein the first yarn guide is a yarn guide wheel, a rim width of the yarn guide wheel is 20-25 mm, an outer diameter of an outer wheel of the yarn guide wheel is 9.4-10.7 mm, and an inner diameter of the groove bottom is 6-7.4 mm; 
 wherein a material of the first yarn guide is ceramic, a surface hardness of the groove bottom of the first yarn guide is 1500-2000 HV; 
 wherein a tow contacts a groove bottom of the first yarn guide in a process of movement, driving the first yarn guide to rotate; 
 wherein the tensioner is a magnetic tensioner; wherein the tow contacts a groove bottom of a yarn guide wheel carried by the tensioner in the process of movement; wherein a setting tension value of the tensioner is 7-10 cN; 
 wherein a linear velocity ratio of the first yarn feeding roller to the second yarn feeding roller is 1.03-1.04. 
 
     
     
       2. The method according to  claim 1 , wherein a tension value of the tow during pre-entangling is 2.5-5.0 cN. 
     
     
       3. The method according to  claim 1 , wherein contents of the carbon black in the polyester POY fiber and the polyester FDY fiber are both 1.2-1.5 wt %. 
     
     
       4. The method according to  claim 3 , wherein an average particle size of the carbon black is 0.3-0.4 μm. 
     
     
       5. The method according to  claim 1 , wherein specifications of the polyester POY fiber and the polyester FDY fiber are both 120 dtex/96f, and a linear density of the black fiber is 232 dtex. 
     
     
       6. The method according to  claim 1 , wherein main process parameters are: a pre-entangling jet air pressure of 2.5-2.9 bar, a pre-entangling jet aperture of 1.5-1.7 mm, a first deformation hot box temperature of 175-190° C., a setting hot box temperature of 150-160° C., a linear velocity ratio of the third yarn feeding roller to the second yarn feeding roller of 1.1-1.14, a setting overfeeding rate of 4.0-5.0%, a winding speed of 500-600 m/min, and a winding overfeeding rate of 2.0-3.0%. 
     
     
       7. The method according to  claim 1 , wherein the black fiber has a breaking strength of 2.1-2.3 cN/dtex, an interlacing degree of 90-100/m, and a coefficient of variation (CV) value of breaking strength ≤6.00%;
 wherein change rates of the breaking strength, the interlacing degree and the CV value of breaking strength of the black fiber produced by a continuous production for 60 days are less than or equal to 10%.